In recent years, wireless ad hoc networks have been developed, which are self-contained distributed networks made up of terminals and do not use base stations or access points. A wireless ad hoc network is configured by connecting a large number of terminals (hereafter, referred to as nodes) capable of performing wireless communication with each other.
In this kind of wireless ad hoc network, each node exchanges a Hello message with different neighboring nodes so as to detect the presence of the neighboring nodes. A node then registers all the detected neighboring nodes in a link table so as to form a link on a duplex path with all of the neighboring nodes. After forming a link between nodes, each node uses the link table to perform a control on communication data forwarding.
An explanation is given here, with reference to FIG. 13, of an example of a link table. FIG. 13 is a diagram that illustrates an example of a conventional link table. As illustrated in FIG. 13, a link table stores therein, with respect to all neighboring nodes (in the example of FIG. 13, the number of nodes is x), “link node ID” for uniquely identifying a neighboring node and “quality information” that indicates the quality of communication from the neighboring node toward the subject node.
As to the examples of conventional technology, see Japanese National Publication of International Patent Application No. 2009-538027, Japanese National Publication of International Patent Application No. 2003-522495, Japanese Laid-open Patent Publication No. 2005-168020, and Japanese Laid-open Patent Publication No. 2007-266697, for example.
However, the above-described conventional technology has a problem in that the size of its link tables becomes large. Specifically, with the conventional technology, because all the neighboring nodes are registered in the link table, the number of entries in the link table becomes large, which results in an increase in the size of the link tables.